The NEC protocol uses pulse distance encoding of the bits. Each pulse is a 562.5µs long with carrier frequency of 38KHz. Logic bits are transmitted as follows: Logic 0: 562.5µs pulse burst followed by a 562.5µs space, with a total transmit time of 1125µs (562.5 x 2). Logic 1: a 562.5µs pulse burst followed by a 1687.5µs (562.5 x 3) space, with a total transmit time of 2250µs (562.5 x 4). The complete extend ...

This is a closed-caption decoder with serial output based on a Microchip PIC16F628A. The internal comparators of the PIC16F628A are used to implement a peak detector and data slicer. The hardware was designed by Richard Ottosen, and the firmware was written by Eric Smith. This closed-caption decoder does NOT overlay captions on video (OSD, on-screen display). If you need a device to overlay captions on vide ...

This project supports both RDS (Europe) and RBDS (USA) Tuner FM band 88..108 MhZ (Europe and USA.) You can choose between a 4x20 character LCD or a smaller graphical LCD to display data. A simple RS232 interface can also be used. A 4x20 character LCD module will display these: 1st row: Station name (PS), Quality, Program Identification (PI), Traffic Program (TP) and Announcement (TA) 2nd row: Time and Date ...

Overview This is a building block project I developed to try out a few ideas. It decodes a 4-bit binary word to outputs that will drive a 7-segment LED display. Functionality is similar to the 7447 BCD-to-seven-segment decoder/driver IC however, because it's implemented using a microcontroller, the segment control data can be customised to display any set of 16 characters you wish to create. It also has ...